The DVD video format has realized continuous reproduction of still pictures (so-called slide show). The respective still picture signals are encoded to an intra-frame picture (I-picture) of the MPEG2 (Moving Picture Experts Group 2) video and multiplexed in a MPEG2 program. By multiplexing the I-pictures with audio data and sub-pictures into an MPEG2 program stream, the audio data and the sub-pictures may be synchronized and reproduced in the slide show. This slide show is reproduced at a preset timing based on the presentation time stamp.
The program stream for the DVD video has a structure with a VOBU (video object unit) as a unit. This conventional DVD data structure is described in, for example, the Japanese Laid-Open Patent Publication H10-271444. FIG. 1 hereof schematically shows the structure of a DVD video program stream of the conventional example 1. Referring to FIG. 1, the DVD video program stream is managed in terms of the VOBS (video object set) as a unit, which is used as a unit in, for example, a workpiece of a motion picture. This VOBS is composed of plural video objects (VOB), and is a unit of data recorded as a set or a group on a disc. The VOB is composed of plural cells, each being a unit for a scene or a cut in, for example, the motion picture. Each cell is composed of plural VOBUs (video object units). The VOBU has the duration of 0.4 to 1.2 second in terms of the moving picture. In this VOBU, there are contained one or more GOPs (groups of pictures) of the MPEG2 format.
The VOBU includes a Navigation pack (N-PCK), as a pack including the management information of VOBU. This Navigation pack is placed at the leading end of each VOBU. The Navigation pack includes VOBU_SRI (VOBU Search Information) and SP_SYNCA. The VOBU_SRI includes a leading address of VOBU reproduced in N seconds (N being an integer) before and after the replay time of VOBU containing the VOBU_SRI. The SP_SYNCA includes the address information of the sub-picture reproduced in synchronism with the video of the VOBU containing the SP_SYNCA. In reproducing e.g. a motion picture, this Navigation pack is first read in and replay is carried out based on the management information specified by the Navigation pack.
The VOBU includes, in addition to this NV_PCK, a video pack (V_PCK), as a pack having the main picture, an audio pack (A_PCK)A, as a pack including the speech data, and sub-picture pack (SP_PCK) S, as a pack including the sub-video data. The V_PCK, A_PCK and SP_PCK are compressed in a preset format, such as MPEG2, and recorded in this form on the recording medium. The VOBU may be exemplified by VOBU1 including a video pack shown for example in FIG. 1 (containing data of one I-picture and Sequence_end_code) and VOBU2 not containing the video pack.
The VOBU, used in the slide show, may not contain the video pack (Video pack containing the MPEG2 video). With the VOBU not containing the video pack, for example, VOBU2 in FIG. 1, the video still from the previous VOBU is continued. The time duration of the continuation of the still display of the I-picture may be controlled by the navigation command.
The program stream of the DVD audio basically has the same structure as the structure shown in FIG. 1. The DVD audio format implements the mode (Browsable slide show) in which the audio replay is asynchronous to the progress of the slide show. In the Browsable slide show, if the user commands the player to proceed to the display of the next still picture by e.g. a remote controller, such that the still display time of each still picture is varied, audio replay is not interrupted, such that audio data is reproduced continuously. Thus, in the DVD audio, there is such a mode in which video replay is not synchronized to the audio replay.
Meanwhile, data of the format different from that of FIG. 1 is stated in the Japanese Laid-Open Patent Publication 2002-158972, filed previously in the name of the present inventors. This Publication is referred to below as a prior-art example 2. The application format of data recorded in the information processing apparatus disclosed in this prior-art example 2 has two layers, namely the PlayList and Clip, for management of the AV stream. The PlayList in the PlayList layer is referenced solely by the user who may refer to the PlayList to reproduce and edit data, such as video data. On the other hand, the Clip layer is used when the player reproduces the AV stream specified by the PlayList. Here, an AV stream and the subsidiary information of the AV stream, paired together, is one object, which is managed in terms of a Clip as a unit. An AV stream file is termed a Clip AV stream file and its subsidiary information is termed the Clip Information file. The Clip AV stream file and the Clip Information file are discretely recorded on a recording medium. The data management is facilitated by discretely recording and supervising the stream data and its subsidiary information.
However, with the data form shown in FIG. 1, the address information is embedded in the MPEG program stream, so that readout becomes time-consuming. That is, in determining the readout address of the still picture, stream data is read out from the disc, the data is analyzed by a host CPU of the player, and the address of the access point of the still picture is subsequently determined, thus protracting the readout operation. If the slide show may be realized using the format similar to that of the audio video data as stated in the aforementioned prior-art example 2, data management may be facilitated, while a recording and/or reproducing apparatus of an analogous structure may conveniently be employed.